First, you read the question it will say:
A set of ten cards, each showing one of the digits from 0 to 9 , is divided up between five envelopes so that there are two cards in each envelope. The sum of the two numbers inside it is written on each envelope. Then when you have read the question write out the numbers like how I’ve done it here.
Decide on one of the answers starting with the
lowest number which in this case it would be 3! We chose to use 5+2!
Then write out on a separate piece of paper the
numbers
1 to 9.
After that cross off the numbers 5 and 9 and keep doing
This for each number until all the numbers on the
separate piece of paper are gone.
Then for your result you will have a sum for each
number, and you should have your answer in front of you.
Now you can solve the others on your sheet.
Solution
3: 0+3
7: 5+2
8:1+7
13: 9+4
14: 8+6
By Sydney and AliceB